"X-Men Origins: Wolverine" is a prequel to, and a bit of a re-boot for, the popular franchise about powerful, cranky, flawed mutants -- and the other mutants who love them. But its story feels slightly malformed itself.

If it's truly an "Origins" tale, as advertised -- well, where are the explanations? When we meet baby Wolverine, he's already on the cusp of mutating -- and has a secret half-brother, Sabretooth.

But why are they mutants? And such different ones? And being raised apart, and in ignorance of their parentage? The story never answers that, which some diehard fans might brush aside in their rush to get to the good stuff.

But neither does the script justify why Sabretooth becomes Wolverine's sworn enemy (or not, depending on the demands of the plot). And other, basic elements -- like why another perfectly harmless mutant is murdered early on -- never become clear.

Before the Marvel maniacs rise up in revolt -- too late, perhaps -- let me tell you, I enjoy a good comic-book movie. And pay no attention to that rough bootleg you might have seen on the internet; the finished "Wolverine" has plenty of eye candy and fine, Hong-Kong-style stunts.

But the sophisticated ironies of "Iron Man"? The human drama of the first "Spider-Man"? The coal-black touches of "The Dark Knight," or even the overreaching ambitions of "Watchmen"? Those aren't here.

They don't have to be in every superhero movie, of course -- no one looked for deeper meaning in "Fantastic Four." But "X-Men" always had a political resonance to it, reflecting on racial prejudice at the comics' debut and, by the time of the first film, suggesting a metaphor for gay rights.

But there's no context or subtext here -- outside of U.S. military bad, mutants cool.

Hugh Jackman returns as Wolverine, of course, and takes up a second job as one of the producers -- which resulted in a shorter commuting time for him (the new film was mostly shot in Australia and New Zealand, instead of Canada) and his choice of Gavin Hood for director.

The first must have been convenient (although if you believe Jackman, the location change was because of his "desire to be challenged"); the second was a bad decision. Hood's few films include the small-scale "Tsotsi," and the painfully obvious flop "Rendition"; he shows no visual sense of place or period here.

Nor does he show any interest in reining in the pumped-up Jackman, who spends much of his time either howling up at the sky (while the camera dizzily pulls back) or muscularly running away from conflagrations (while things blow up behind him).

Luckily, you have the rest of the cast -- particularly Liev Schreiber as Sabretooth, Wolverine's brooding nemesis.

Of course, the script never makes their animosity plausible, so Schreiber -- the best actor on board -- has to do the job all himself. Luckily, he's up to it, creating a monster of bottomless brooding and endless, unmotivated malice. He's like Iago, with claws.

Ryan Reynolds is good, too, as the swordsman Wade Wilson, and as Agent Zero, Daniel Henney pulls off some of the kind of gunplay Chow Yun-Fat used to. (Only Taylor Kitsch, sadly, disappoints as Gambit, coming off as a second-rate magician.)

So does the film succeed, overall? On some levels. After two flops, it gives Jackman a much-needed moneymaker. It gives Fox -- always a franchise-oriented studio -- another series. (Although really, how many other X-Men deserve their own origins story?) And it gives rabid Wolverine fans another episode.

And if you don't match any of those demographics? And all you want is a guilt-free, sci-fi summer pleasure? Save your money and wait another week. The crew of the Enterprise is on its way.